Joaquin Phoenix and Philip Seymour Hoffman in a scene from “The Master.” (MCTeye)

The first hour of Paul Thomas Anderson’s “The Master” contains some of the most rapturous filmmaking of the year.

The time is post-World War II America. The streets gleam with hope and possibility. Freddie Quell (Joaquin Phoenix), an emotionally disturbed loner who already had trouble fitting in with his fellow sailors in the Navy, has landed a job as a portrait photographer at a swanky department store. The superb cinematographer Mihai Malaimare Jr. (“Tetro,” “Youth Without Youth”) lights the set like a cathedral of luxurious capitalism, filled with shopping racks of material pleasures. A model approaches customers, parading her jade-green outfit (“Only $49.99,” she says with a smile). The store is a symbol of the national state of mind: You can practically smell the perfume being pumped in through the air conditioning vents.

But Freddie, who is deeply troubled, doesn’t fit in and doesn’t last long at the job. In the darkroom where he develops his pictures, he has sex with women and chugs down hooch he makes out of photo-processing chemicals. When he smiles at customers, his expression resembles a snarl. Finally, inevitably, he loses his cool and attacks a man posing for a portrait. He doesn’t just punch the poor guy: He berates him, embarrasses him, bullies him, working out some sort of undefined, unquenchable anger.

Phoenix, who hadn’t acted in a movie since 2008’s “Two Lovers,” has played crazy, dangerous men before. But his performance in “The Master” renders everything he’s done up to this point in his career as a backstage warm-up, practice exercises for the real thing. Freddie moves with the speed and swagger of a drunk walking into a bar fight. His gaunt face is plaintive and inscrutable: He longs for something, but even he can’t tell you what it is, and that yearning has curdled into a pattern of self-destructive behavior.

Anderson shoots the actor’s face from angles we haven’t seen before. His eyes, mistrustful and shifty, at times seem to be the color of ebony, but you’re not sure if they are radiating hatred or an inner deadness. He is a fascinating creature, and Phoenix’s performance is without question the best of the year thus far.

Then Freddie meets Lancaster Dodd (Philip Seymour Hoffman), a rotund, fast-talking man constantly surrounded by people who treat him like a sage, hanging on his every word, laughing at all his jokes. Lancaster describes himself as a “doctor, writer and theoretical philosopher.” He is married to Peggy (Amy Adams), a friendly woman who is much more aware than she initially seems. He has a son, Val (Jesse Plemons), who regards his father with a vague air of disdain. Lancaster also has a daughter (Ambyr Childers) about to marry a man (Rami Malek) who, like everyone else in their circle, regards Lancaster as a genius.

Lancaster and his cult ― there’s really no other word to use for them ― were inspired by L. Ron Hubbard and Scientology. That word is never used in the film; instead, it’s “The Cause.” But the way in which Lancaster draws the wayward Freddie into the fold ― with a series of questions and psychological tests called “Processing” ― were clearly inspired by the controversial church. Several of the plot points in the movie, including Lancaster’s brief arrest, were lifted from Hubbard’s life.

But Anderson doesn’t commit to the inspiration for his movie; he doesn’t commit to anything, really. You walk out of “The Master” baffled and frazzled, wondering what this sumptuous, commanding movie was trying to say or why it was even made. I can’t think of a single reason, other than to provide a showcase for actors.

The film belongs to Phoenix, but Hoffman more than holds his own, the camera coming in close on his jolly red face, his friendly laughter ringing with manipulation and falseness. Freddie, whose father is dead and whose mother is institutionalized, is understandably drawn to this man, who promises answers and inner peace and happiness, and even claims to be able to cure leukemia. Lancaster has written a book his followers view as a sort of bible. He loves to entertain and hold court, and there’s more than a trace of huckster to him (“He’s making it all up as he goes along,” Val casually confides to Freddie in one scene).

Anderson sets everything up so well, you wait for the plot to kick in so “The Master” can start to cook. Instead, nothing happens. There are incidents. Lancaster and Freddie spend a night in adjacent jail cells, the bars the only barrier that keeps them from tearing into each other. In one mystifying scene, the women at a house party all suddenly lose their clothes while Lancaster sings a song. Did this really happen, or is Freddie imagining it? Freddie’s sexual addiction, which was stressed in the early stretch of the film, suddenly disappears.

In terms of style, “The Master” eschews the flashy style and peripatetic camera of “Magnolia” and “Boogie Nights.” Most scenes are played out in contained spaces, and the emphasis is on performance, as it was in “There Will Be Blood.” But Daniel Day-Lewis’ character of Daniel Plainview was large and complex enough to hold the movie together. He had mythical dimensions.

In “The Master,” Freddie seems to shrink and become less interesting as the movie goes on, and Anderson throws in interludes, like a long scene in the desert or an interminable sequence in which Freddie is forced to pace in a room, that slow the pace to a slog. For the first time in his career, Anderson bores you.

Some critics have championed “The Master” as an intentionally elusive and mysterious movie, but I think that’s a cop-out, a fancy way of saying Anderson couldn’t fully convey the ideas in his head. The movie poses questions about the importance of faith, religious or otherwise, how far the human capacity for change can stretch and whether there is such a thing as emotional damage so profound it can never heal. But these are hardly new thoughts, and the picture is too timid or reluctant to explore them in depth.

By film’s end, “The Master” has become a contest between two gifted actors trying to shout each other down. The commitment to their roles is impressive, but it’s tethered to a weightless, airless movie, a film so enamored of itself, the audience gets shut out.